Electrical sound recording and reproducing apparatus



June 10, 1930. c. HUENLICH 1,762,175

ELECTRICAL SOUND RECORDING A ND REPRODUCING APPARATUS Filed Oct. 13, 1928 5 7 FIGQZ INVENTOR ChflAZLL-IhAflwiubhz TORNEY Patented June 10, 1930 UNITED s'rArl-zs PATENT .oFr'lcscmanns HUENLIOH, or BLOOMFIELD, new macaw, 'assrenon 'ro rnomas A. EDISON, mcoaronarnn, or wnsr onanan, NEW Juan, A coaromrron or NEW mass? ELECTRICAL scum: nnconnmc AND nmaonucme APPARATUS Application filed October 13, 1928. Serial No. 312,228.

This invention relates to electrical sound recording and reproducing apparatus and more particularly to a combined unit for, electrically recording or reproducing sound for use with phonographs of "the dlctating machine type. p It is an object of thisinvention. to rovide apparatus of the class described which will electrically record and reproduce sound in connection with the hill and dale records of the type used on dictating machines with a high de ree of ualitya It is a urther 0 ject of this invention to provide apparatus of the class described in which extraneous noises and distortion in the recording and reproduction is eliminated or reduced to a minnnum.

. It is a further object of my invention to provide apparatus of the class described which is-simple and economical to construct I and rug ed and reliable in operation.

Still irther objects of my inventiomwill be apparent from the s ecification.

to be characteristic of my invention are set forthwith particularity in the"-'-appended The features of'nove ty which I believe claims. My invention itself, however, both as to its fundamental principles and as to its particular embodiments, will best he un-' derstood by reference to the specification and accompanying drawing, in which Figure 1 is a side elevation of a recorder and reproducer according to' my invention, shown in position for recordin Figure 2 is a similar view 0% the apparatus shown in position to reproduce;

Figure 3 is a bottom plan view of the apparatus shown in Figures 1 and 2, and

Figure 4 is an: exploded perspective view of the recorder frame and reproducer lever assembly. I

In accordance with my invention, I provide a frame arranged to be attached to the usual traveling arm or carriage (not shown) of a dictating machine. The frame carries a magnet havlng pole pieces defining prefer-V ably a plurality of air gaps in whichthere is provided. an armature mounted for vibration.

The frame carries below a pair of floab 'ed to the vibratin 1 lever is normally that when engaged with the record a vibrabase 1 and is -means of bolts 4 and 5. The flange 3 may be ingsu portspreferably arranged one above the ot er and preferably pivoted about acommon axis for vibration in a c lindrical plane. On' the upper of the sai floating supfiiorts there is provided a lever arm pivota 'the record, one for recording, the other for reproduction. One of the levers is connectarmature. The other ee but is so arranged as y mounted for vibration and carrying at one end a stylus or jewel for engaging o tion-transmittmg connection is established by it and the other lever in such a manner that vibrations are transmitted to or from i the armature. v v

-, Referring now more particularly .to the figures, 1 designates a frame or base ar-. ranged to be attached to the usual traveling arm or carriage (not shown) of a dictating machine and carrying a magnet support 2,

which is preferab y in the orm of a sheet of metal of suflicient strength having a horizontal flange portion 3, which engages the old thereon,.for example, by

provided with slots to permit of adjusting the position of the magnet. The magnet 6 is provided with a pair of pole pieces 7 and 8, so formed as to provide pole tips 9, 10,

11 and 12. An armature 13 is mounted for vibration between said pole pieces. A coil 14, whichmay be wound upon a suitable form,,is provided surrounding armature 13.

If desired, a sheet of conducting material such as copper or the like 15 may be provided over the top of the coil. The armature 13 is preferably cylindricalifclxcept at its upper end, where it maybe made relatively thin and flat as at 16 and is extended be yond the air gap for a purpose which will later be described. To provide damping of the armature, a strip off rubber 17 may be positioned between the end of the armature 16 and pole pieces 9 and 11.

The armature is carried by a strip 18,

- preferably of non-magnetic material such as brass, having ears 19 and 20 .bent over the pole pieces. A spring 21, whlch may for example be phosphor bronze, is secured by means of bolts 23 to they ears 19 and 20,

and insulating material such as strips 22 of 10 bakelite are interposed between the cars 19 and 20 and bolts 23, which secure the spring 21 in position. The lower end of the armature ma have a shoulder formed thereon so that 1t may be secured in the spring by 15 passing a collar 24 around the projecting end of the armature. The lower end of the armature projecting below the collar may then be upset as at 25, thereby securing the ,armature in position. The pole pieces may 20 be laminated and secured together in any suitable manner, as, for example by rivets 71, and the entire magnet assembly may be secured to the member 2, as, for example, by means of bolts 7 O, as suflicient clear- I ance is preferably allowed to permit of adjusting the magnet assembly on the member 2.

The base 1 is provided on its under-side frame 31. provided with arms 36 and .37. re-

The-

inforced by a cross brace and bolt 50. open ends of said arms are pivoted as at' 36 and 37 to permit the carrier frame 31 to have a certain amount of movement in a vertical plane. The carrier frame 31 is provided with means for mounting the recorder arm. This may be in the form of downwardly extending ears 39 and 40, carrying bearlng screws 41 and 42, which screws may be provided with tapered inner ends to engage tapered depressions in arms 43 and 44, secured to the recorder arm 30. The freeend of the recorder arm 30 is provided with a stylus or jewel 45 for engaging and engraving the record; the other end 46 is pivotally connected to link 26, which, in turn, ispivotally connected at its upper end to block 47, secured in the end of armature 13. The recorder assembly 28 may be provided with a block 53, serving to increase the weight of the recorder assembly to the desired value; The reproducer assembly 29 preferably consists of a ring 54 secured to carrier block 55, which is, in turn, pivoted between arms 34 and 35. The ring 54 may be fitted with an inner assembly secured in position by means of screws or bolts not shown and forming an inner ring 56, provided with bearing screws 57 and 584 The reproducing lever is preferably in the form of a ring 59 and carries, as at point 60, a suitable stylus or jewel. The ring 59 is somewhat smaller in radius than the free end of recording lever 30 and is placed in osition with the free end of the recording ever extending throu h it. The reproducing lever 59 is normal free, that is to say, there is no connection etween it and armature 16-.

In the operation of the apparatus according to my invention for the purpose of recording sounds upon a record, the recording and reproducing assemblies are both disengaged and allowed to swing downward until the recording stylus 45 engages the surface of the record. Under such conditions, the reproducing support swings downwardly to the full extent of its motlon, while the recorder assembly swings downward untilthe recording stylus makescontact with the record. If speech currents derived from a suitable microphone or other source are now supplied to the coil 14, the armature will be vibrated and the vibrations'thereof transmitted through link 26 tothe recording lever, and the stylus will engrave the surface of the record in, accordance therewith; at the same time, the floating support permits the stylus to follow irregularities in the surface of the record without adversely affecting the recording of sounds therein. 1

When it is desired to' reproduce sounds, the reproducer assembly is permitted to swin downwardly 'while the recorder assemb y 28 is prevented from so doing, as, for example, by the inter-position of dog 51 under tongue 52 of the recorder assembly. The dog 51 is manually operable in a manner well known in the art by means of a pivotally-mounted lever (not shown) which may be carried by the usual traveling arm or carriage of the dictating machine so that the dog may be easily brought into or out of enga ement with. the tongue 52 at the will of t e operator. As the reproducer assembly swings downwardly, the portion of ring 59 opposite the re roducer stylus 60 engages the upper side 0 the free end oi the recording lever 30, thereby rotating the ring '59 in counter-clockwise direction until the stylus 60 engages the record. As the record passes under the stylus, it will be raised and lowered in accordance with the vibrations engraved upon the record, and the opposite side of the ring will transmit these vibrations to the recording lever 30, which, in turn, transmits them to armature 13 through link. 26. The floating support for the ring 59 permits the axis thereof to use and fall to eliminate the efi'ect of irregularities inthe surface of the record or in the shape of the mandrel on which it is mounted, while at the same time the vibrations are transmitted to the recording lever and frame, a recording lever carried b changes may thenceto the armature. The vibrations of the armature, as will be understood, vary,

the flux through the coil and generate currents corresponding closely to the vibrations of the reproducin stylus. Such currents may be converte into sound by the use of a tele hone receiver connected to the coil, or, if esired, they may be amplified and supplied to a loud speaker.

For the purpose of providing an adjustable stop limiting the downward motion of the reproducer assembly, the screw 61 may be passed through the .ring frame 27 between the arms 34 and 35 in such a manner as to be en aged by the upper side of block 55. It wil be understood that by varying.

the position of screw 61 it is possible to control the amount of free movement of the reproducer assembly.

' While I have shown and described certain preferred embodiments ofmy invention, it

will be understood that modifications and be made without departing from the spirit and scope of m invention, als twill be understood by those s 'lled in the a 1 I claim 1. An electrical sound recorder and reroducer, comprising, in combination, a rame, a pair of floating supports pivotally tion mounted for vibration in said gap, a connection between said armature and one ofsaid levers for transmitting vibrations between said armature and said lever, and

means for transmitting vibrations between said levers under predetermined conditions.

2. An electrical sound recorder and re-- 'mounted on said frame, a recording lever mounted on one of s'aid supports for oscillation thereon, a reproducing lever mounted on the other of said su ports for oscillation I so thereon, said levers being alternatively engageable with a record,-a magnet mounted on said frame, a pair of pole pieces mounted on said magnet and defining an air gap,

an armature mounted forvibration in saidgap and biased to-neutral' position, a connection between said armature and one of said'levers for transmitting vibrations therebetween, and meansfor establishing a vibration-transmitting connection between said --levers,when desired.

3. An electricah'soundredorder and reproducer comprising, in combination, a

frame, a reproduc lever carried y said frame, saidlevers being arranged for selecv tive engagement with a record, a. magnet mounte on said frame, pole pieces mounted on said magnet to form an air gap, an armature mounted for vibration in said air gap, and a connection between one of said levers and said armature for transmittin vibra- ,tions therebetween; said levers -be1 said supports,'a reproducinglever mounted on the other of sai supports,-said levers being arranged for selective engagement with a record, a magnet mounted on said frame, pole pieces mounted on said magnet to form an air gap, an armature mounted for vibra-' tionin said air gap, and a connection between said armature andone of said levers. .for transmitting vibrations therebetween,

said levers being so arranged that when the other of said levers is engagedwith said record, a vibration-transmitting connection is established between said levers.

' 5. An electrical sound recorder and reproducer, comprising, in combination, a frame,

a. pair of supports carried thereby, a recording lever mounted for vibration on one 4 of said supports and a reproducing lever mounted on the other of said supports, a magnetmounted on sii having pole pieces defining an air gap, an armature mounted for vibration in said gap and a connection between said armature and one of saidlevers, the other of said levers being normally free and so arranged as'to be maintained in vibration-transmitting contact with the first of said levers when said other lever is engaged with said record.

6. An electrical sound recorder and reproducer, comprising, in combination, "a

frame, a pair of su ports carried by said frame, a recordin of said supports or vibration thereon, a reproducing" lever mounted on the other of said supports for vibration thereon, a ma net mounted on said frame and having po e' pieces defining an air' gap, an armature id frame and ever mounted on one mounted for vibration in said air gap and a connection between said armature and said recording lever, said/reproducing lever being normally free aitdbein'g arranged to be maintained in vibration-transmitting relation with said recoi'ding lever when said reproducing lever is engaged .with a record.

7. An electrical sound recorder and re.-

. n u -u a i producer, comprising, in combinatapn, a

rame, a pair of floating su orts carried by said frame, one below the'ot er, a recording lever pivotally mounted onltli'e upper supi r a pair of floating supports carried by said port for vibration thereon, a reproducing lever pivotally mounted on the lower support for vibration thereon, a magnet mounting lever when said reproducing lever is in contact with a record.

8. An electrical sound recorder and repro ducer, compr1s1ng,- 1n combmation, a frame,

- frame, one below theother, a recording lever pivotally mounted for vibration on the upper support, a reproducing lever pivotally mounted for vibration on the lower support, said levers being selectively engageable with a record, a magnet mounted on said frame, an armature mounted for vibration in the field of said,magnet, and a connection between said armature and said recording lever, said levers being so arranged as to be out of engagement when said recording lever is engaged with a record, and in contact whensaid reproducing lever is engaged with a record. c

. 9. An electrical sound recorder and reproducer, comprising, in combination, a

rame, a pair of floating supports carried by said frame, one below the other, av recording lever pivotally mounted for vibration on the upper support, a reproducing lever pivotally mounted for vibration on the lower support, said reproducing lever having "a portion extending above said recording lever, said levers being selectively engageable pith a record, a magnet mounted on said rame, in the field of said magnet, and aconnection between said armature and said recording lever, saidlevers being so arranged that said reproducing lever engages the upper side of said recording lever when said reproducing lever is engaged with a record.

10. An electrical sound recorder and reproducer, comprising, in combination, a frame, a pair of floating supports carried by said frame, one below the other, a recording lever p votally -mounted for vibration on the upper support, a reproducing lever in the form of a ring pivotally mounted for vi- I bration on the lower support and encircling said recording lever, said levers being selectively engageable with a record and having stylus points on opposite sides of their fulera, a magnet mounted on said frame, an armature mounted for vibration in the field of said magnet, and a connection between said armature and said recording stylus, said re'producin lever being normally free."

11. An e ectrical sound recorder and rean armature mounted for vibration roducer, com rising, in combination, a

rame, a pair 0 floating supports carried by said frame, recording and reproducing levers carried by said supports respectively, a magnet, an armature mounted for vibration in the field of said magnet, and with which each of said levers is arranged to have vibration-transmittin connectlon, and means for establishing an tive at will vibration-transmitting connection between said armature and one of said levers.

This specification signed this 12th day of October, 1928.

7 CHARLES HUENLICH.

for rendering inopera- 

